Steam cylinder lubricating oil



United States Patent STEAM CYLINDER LUBRICATING OIL Robert J. Leygonie, Notre-Dame, and Bernard l 3 de Saint Leger, Paris, France, assignors-to Esso Standard S ociete Anonyme Francaise, Paris, France, a body corporate N0 Drawing. Application April 23, 1952, Serial No. 283,970

Claims priority, application France August 18, 1951 3 Claims. (Cl. 196-151) his h en eh, e a es. 9 tea th. hyi hde i lh reh h q i and he a rheess e t heir PIQPQ T IiQ k, he tie r y the invention relates to mineral oils having high temperature and volatility characteristics which renderthem suitable for the lubrication of steam cylinders.

Steam cylinders in use in modern technology may be generally divided into three groups; saturated steam cylinders, operating at temperatures in the neighborhood of 300 to 320 C., moderately superheated steam cylinders which operate at 300 C. to 350 C., and highly superheated steam cylinders operating at temperatures in excess of 350 C.

Steam cylinder lubrication is ordinarily accomplished by introducing a lubricating oil with the steam (atomization) or by injecting the oil into the cylinder through small orifices in the cylinder, or by a combination of both techniques. It is to be seen, therefore, that steam cylinder lubricating oils are subjected to extremely severe conditions. They must possess heat stability char acteristics such as to prevent their decomposition'to tar or coke under prolonged high temperatures and to minimize tarry and sticky residues often deposited on the various lubricated parts. They must possess good low temperature properties in order to ensure circulation in the lubrication system at low temperatures. They must be sufliciently low in volatility to prevent entrainment and escape with steam during exhaust,

Cylinder oils are ordinarily highly refined mineral oils which may or may not contain incorporated therein various qr d or c -O id z d tt s. he h herh Qi s a e mainly o h e di in t t e Ty e D ti la on d es ht li l-thhh h ev ae tfihie' e h Pehel hm (pr eip i y Pe hsy rehie h ir?- e eit e ea d nh wit s lf i a id:

T e iscou d l ete Qh hihee unde hi h at-hu a d r not th s fh ie h i l r se eeti e. eive ts nd, if neee ar e h Ty e. The ht s ak 0 h ,ei esl e h der ls obtained by propane deasphalting of distillation residr es from asphalt-base crudes. These propane-extracted oils re enerall refined by the. usu meehs hifh e aeid, seiee i e selveht l a d dewaxe t The rt s e e ally ound that 1 13? tree 1 ails t is hese hem the heh-e 'hhit ha e n e Pehh h veh ru e are ui ab e or t e hh eati h. i. hi hl su e heated e m c lind s, O s Q e 2 Q1, h re e t r pidl e treihe er iv tarry or ehhe. deligh s Qi th h e te P si hei eves w. he 39 s a eek e e a n h mel e le wei ht e efhnie haetiq h vesl he et f re o be Present nl in the Penns lvan a. t pe ent ies- It has now b en ound 1 .14 t nne the hieet h thi ihveh oh hat thes ee thh hi h mhleehlhr Wi h ar fihie e hh t re ef er r re o a re h may he erheete r m Other etu s urce e he h t Pennsylvania crudes and combined with mineral oils to ha st am ind r e i w ch ha e t t nd i tempe at e eher et f sties 2,764,529 Patented Sept. 25, 1956 Briefly stated the instant invention comprises treating an asphalt with a liquid mixture ofbutane" and propane to extract the paraffinic andnaphthenic components therefrom, treating the raflinate with a solvent that is e eqtr e th hhhht e e s th h a e te h a a h hly ereihhi ree hhe m i l u a or ombin h w th highly r ed. min r l Oi to P re ee i esh tions suitable for the lubrication of steam cylinders The asp al r e h hie materi l w ic s uses a tee m er a ma an s hal d m eer r p oleum Whet er f mv eeuhih d t i i h hea a propane deasphalting process. It is of especial note that asphalts obtained from such crudes as Venezuelan crudes or Arabian crudes are suitable starting materials.

The mixture of butane and propane may be varied; between limits ofabout 10% propane to 30%, propane preferably 15;%v to 20%, percentages being by volun e. The propane tends to reduce the solvent power of the butane and tends. to. limit the solvating effect to those. components of the asphalt that are desirable. To.- use more than about 30% of propane would reduce the sql: vent power of the mixture. to the point where the heayier fractions would not dissolve and to use less than about 10% would increase the solvation eifect of the mixture to a point where undesirable components would be exhe e rom h hal eemehh of el e h mixture which s use?! t9 ethe the' s eh ba y e t een h h r lh he an 15 imes Phefe hlY 0 9 2 V l deren'dih upon the component parts of the asphalt. The te rnpera ture of the treating step should be maintained at one within a range from -20 C. to 120 C., the preferred te per tu e ran he hg ehqht 03 C- to .0 Any of the mm kn w he hes s o ea her-ins. s eh e e h terehrheht a ita r-S miti ui m ehe h ike they be il ed in s. e hetihh feP- T e re fihete' hh he hhtehe-p ehme h l h s then. hea ed. w th e olv nt ha selehh f th hhphthehie eehst thehts ou h if is referr d he u e anhydrous phenol it is also within the concept of invention to use any of the naphthene selective solvents known in the art such as light hydrocarbons, ketones, chlorinated solventsv and the like. If desired, a dewaxing solvent may also. be incorporated into this naphtheneextra ti n. s ep- The resulting resinous material containing molecular weight paraflins and excluding any naphthen'ic constituents which are notably heat unstable, may be blended with various known highly refined mineral; oils, to obtain a steam cylinder lubricant. For example, one may use as a base stock a phenol-treated propane he e th, hem 10 h- 40 hr v me h i us hh ehi o btain e hi heee h steam der'qi Percentages of the resinous material of frorn 15% to hr hihme are sn e e iy ie r d- In order to test the composition of the instant inven; her; a. testin p eeed re wa p rfo me n e ehqrh ap ara us he resi eih the ndi ns of tempe ature a pressure prevailing in steam cylinders, (Cf. Banceliri S. N. C. F. method, Rev. Gen. Chim. de Fer. 11/1/37.) This testing procedure is as follows: 7 I gr. of the test oil are poured into a calorimetric bomb which is placed along with a small superheater coil into an electric oven. Steam at 12 kg. pressure and p h ed 9 the tem e ature e t e te t is bubbled h g h oi f r hre our the Q being a the stehih. empera ure Th eh rei ih t am P s e a a uniform rate such that after three hours three liters of liquid can be collected (condensed water plus entrained PT QW' L Finally, the unentrained residue in the vessel is weighed. The oil passes the test at a given temperature, it at this temperature, the following observations are made:

(1) At least 7 gr. of residue remains. (2) This residue is oily or greasy and does not contain hard matter (coke).

It is to be noted that steam cylinder oils of type 1 above pass this test easily at 400 C. Neither type 2 nor type 3 oils pass the test at 380 C.; type 2 failing at 350 C. A number of oils prepared according to instant invention have successfully passed this specifically designed test for steam cylinder lubricating oils. The preparation of these oils are set out in detail below.

Example 1 Density of 15 C 0.975 Saybolt Universal viscosity at 210 F 1113 This oil was treated with 9.5 volumes of phenol in four stages under the following conditions:

}oil No. 1

1st treatment: 2 volumes of anhydrous phenol at 75 C. 2nd treatment: 2 volumes of anhydrous phenol at 85 C. 3rd treatment: 3 volumes of anhydrous phenol at 85 C. 4th treatment: 2.5 volumes of anhydrous phenol at 90 C.

A rafiinate was obtained in 40% yield having the following characteristics:

Density at 15 C 0.924 Saybolt Universal viscosity at 210 F 567 An oil of type 3 was prepared by deasphalting a Mid- Continent reduced crude with 10 volumes of propane at 45 C. The oil thus obtained was treated with phenol up to a viscosity index of 101. Its Saybolt Universal viscosity at 210 F. was 240. This oil is designated oil No. IV.

}oil No. II

The following mixture was made:

Oil N0. IV 70% by vol. Oil No. II "30% by vol. HI

Oil No. IV gave, in the test mentioned above, a negative result at 385 C.

On the other hand, oil No. 111 gave, at 395 C., 10 gr. of an oily residue, and, at 400 C., 7 gr. of a residue having the appearance of a very thick brown-black oil.

Example 2 An Arabian reduced crude having an Engler viscosity of 30 at 100 C. was deasphalted with propane at 45 C. and gave an asphalt having a penetration of 25 at 25 C. (A. S. T. M. D -25).

This asphalt was dissolved in volumes of commercial liquid butane containing 15% propane.

The butane at 30 C. precipitated the asphaltenes and a viscous oil was separated from the butane layer. It is characterized as follows:

Density at 15 C 0.999

Saybolt Universal viscosity at 210 F 1600 011 V Oil V was treated with anhydrous phenol under the following conditions: 1st treatment: 2.0 volumes of phenol at 75 C. 2nd treatment: 2.5 volumes of phenol at 85 C.

A yield of an oil was obtained having the following characteristics: Density at 15 C 0.946

Saybolt Universal viscosity at 210 F 868 i VI This oil was mixed with oil No. IV in the following proportions: Oil No. IV "70% by vol. on No. v1 30% by vohi VII Cylinder oil No. VII thus obtained gave the following results in the test:

Gram residue At 390 C 13 At 400 C 6 In order to show the deleterious effect of the naphthenic constituents, removed by the phenol treating step, the following example is given:

Example 3 The mixture Percent by volume Oil No. I 30 Oil No. IV 70 when tested, gave at 390 C. 10 gr. of residue which was black and asphaltlike. At 395 C. only a carbonaceous residue was obtained.

It is readily seen from the foregoing examples that the materials prepared by the concept of instant invention are outstanding in their utility as steam cylinder lubricants. Materials prepared by the butane-propane extraction of asphalts followed by the removal of the naphthenic constituents from the raflinate by phenol treatment, contain the high molecular weight paraffim'c resins which enable a type 3 oil to withstand stringent requirements existing in the high pressure steam cylinders.

To summarize briefly, this invention comprises the preparation of a steam cylinder lubricant by the steps of treating an asphalt with a mixture of butane and propane containing from 10% to 30% by volume of propane and treating the rafiinate thus obtained with a solvent that is selective for the naphthenic constituents thereof. The resulting composition composed primarily of high molecular weight paraffinic materials may be blended with refined mineral oils to prepare steam cylinder lubricants having outstanding qualities of high temperature resistance, resistance to steam entrainment and viscosity characteristics. It is to be noted that in accordance with the instant invention the asphalt used as a starting material may not only be the straight run asphalts, that is, the residuum of asphalt base crude, but may also be the asphalts obtained by deasphalting oils such as those obtained by precipitation with propane or propane-phenol mixtures. It is, therefore, possible according to the instant invention to propane deasphalt a crude petroleum, treat the rafiinate by subsequent refining techniques to obtain a refined mineral oil base stock, treat the asphalt by the process of this invention to obtain the resinous materials desired, and combine the two to greatly increase the yield of steam cy inder oils desirable.

What is claimed is:

1. A steam cylinder lubricating oil comprising a propane-deasphalted phenol treated Mid-Continent reduced crude containing combined therewith from 10% to 40% by volume of a high molecular weight parafli-nic material obtained by treating an asphalt with from 10 to 12 volumes of a liquid mixture of butane and propane containing from 10% to 30% by volume of propane at a temperature within a range from 70 C. to C. to obtain an extract containing both paraifinic and naphthenic components, extracting the extract thus obtained with anhydrous phenol, and obtaining therefrom said high molecular weight paraffinic material as a raifinate.

2. A steam cylinder lubricating oil comprising a highly refined mineral lubricating oil containing combined therewith from 10 to 40%, by volume of a high molecular weight paraifinic material obtained by treating an asphalt with a liquid mixture of butane and propane containing from 10 to 30% by volume of propane to obtain an extract containing both paraflinic and naphthenic components, extracting the extract thus obtained with a solvent selective to the nap-hthenic components and obtaining therefrom said high molecular weight paraffinic material as the rafiin'ate.

3. A steam cylinder lubricating oil comprising a propane-deasphalted reduced crude containing combined therewith from 15 to 35% by volume of a high molecular weight parafl'inic material obtained by treating an asphalt with from about 5 to 15 volumes of a liquid mixture of butane and propane containing from 15 to 20% by volume of propane to obtain an extract containing both paraffinic and naphthenic components, extracting the extract thus obtained with a solvent selective to the naphthenic components and obtaining therefrom said high molecular weight paraflinic material as the raflinate.

References Cited in the file of this patent UNITED STATES PATENTS 1,988,712 Bray et al Jan. 22, 1935 2,081,496 Merrill May 25, 1937 2,165,432 Whiteley July 11, 1939 2,168,258 Fisher Aug. 1, 1939 2,339,898 White et a1. Jan. 25, 1944 FOREIGN PATENTS 117,653 Australia Nov. 4, 1943 

1. A STEAM CYLINDER LUBRICATING OIL COMPRISING A PROPANE-DEASPHALTED PHENOL TREATED MID-CONTINENT REDUCED CRUDE CONTAINING COMBINED THEREWITH FROM 10% TO 40% BY VOLUME OF A HIGH MOLECULAR WEIGHT PARAFFINIC MATERIAL OBTAINED BY TREATING AN ASPHALT WITH FROM 10 TO 12 VOLUMES OF A LIQUID MIXTURE OF BUTANE AND PROPANE AT A TAINING FROM 10% TO 30% BY VOLUME OF PROPANE AT A TEMPERATURE WITHIN A RANGE FROM 70* C. TO 100* C. TO OBTAIN AN EXTRACT CONTAINING BOTH PARAFFINIC AND NAPHTHENIC COMPONENTS, EXTRACTING THE EXTRACT THUS OBTAINED WITH ANHYDROUS PHENOL, AND OBTAINING THEREFROM SAID HIGH MOLECULAR WEIGHT PARAFFINIC MATERIAL AS A RAFFINATE. 